1. Write a query to display the following for those employees whose manager ID is less than 120:
   – Manager ID
   – Job ID and total salary for every job ID for employees who report to the same manager
   – Total salary of those managers
   – Total salary of those managers, irrespective of the job IDs

	SELECT manager_id,job_id,sum(salary)
	FROM employees
	WHERE manager_id < 120
	GROUP BY ROLLUP(manager_id,job_id);

2. Observe the output from question 1. Write a query using the GROUPING function to determine
   whether the NULL values in the columns corresponding to the GROUP BY expressions are
   caused by the ROLLUP operation.

	SELECT manager_id MGR ,job_id JOB,
	sum(salary),GROUPING(manager_id),GROUPING(job_id)
	FROM employees
	WHERE manager_id < 120
	GROUP BY ROLLUP(manager_id,job_id);

3. Write a query to display the following for those employees whose manager ID is
   less than 120 :
   – Manager ID
   – Job and total salaries for every job for employees who report to the same manager
   – Total salary of those managers
   – Cross-tabulation values to display the total salary for every job, irrespective of the
     manager
   – Total salary irrespective of all job titles

	SELECT manager_id, job_id, sum(salary)
	FROM employees
	WHERE manager_id < 120
	GROUP BY CUBE(manager_id, job_id);

4. Observe the output from question 3. Write a query using the GROUPING function to determine
   whether the NULL values in the columns corresponding to the GROUP BY expressions are
   caused by the CUBE operation.

	SELECT manager_id MGR ,job_id JOB,
	sum(salary),GROUPING(manager_id),GROUPING(job_id)
	FROM employees
	WHERE manager_id < 120
	GROUP BY CUBE(manager_id,job_id);

5. Using GROUPING SETS, write a query to display the following groupings :
   – department_id, manager_id, job_id
   – department_id, job_id
   – Manager_id, job_id
   The query should calculate the sum of the salaries for each of these groups.

	SELECT department_id, manager_id, job_id, SUM(salary)
	FROM employees
	GROUP BY
	GROUPING SETS ((department_id, manager_id, job_id),
	(department_id, job_id),(manager_id,job_id));